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MoM Lead Conversion SQL
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MoM Lead Conversion SQL

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the month-over-month growth in solar lead conversions for the California market.

Use the conversion date to determine each month. Include months with zero conversions between the first and last California conversion month, and return NULL growth when the prior month has zero conversions or does not exist.

Output

  1. One row per calendar month, ordered chronologically.
  2. Columns: conversion_month, conversions, prior_month_conversions, and mom_growth_pct.
  3. Report growth as a percentage rounded to two decimal places.

Schema

solar_leads
ColumnTypeDescription
lead_idPKINTUnique identifier for the solar lead
market_idINTMarket associated with the lead
lead_created_atTIMESTAMPTimestamp when the lead was created
converted_atTIMESTAMPTimestamp when the lead converted
markets
ColumnTypeDescription
market_idPKINTUnique identifier for the market
market_nameVARCHAR(100)Market name used for reporting
state_codeVARCHAR(2)Two-letter state code when applicable
Tablessolar_leadsmarkets
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